Great for operator stations, material request, call lights, machine monitoring and more. Warehouse use for workstations, inventory replenishment systems. Great for any machines needing simple operator attention. Can be used for cycle timing alerts, changeover timing, downtime status, maintenance acknowledge and more. Light Source: RED/GREEN 2 layer stack light, 12 light beads on each layer, compared with tungsten bulb, it has a brighter and eye-catching light and longer working life